The aim of the research was the evaluation of wastewater management in
terms of stability and efficiency of wastewater treatment, using
statistical quality control. For this purpose, the analysis of the
operation and operation of the “Kujawy” Sewage Treatment Plant was made,
which is one of the most important and largest sewage management
facilities in the city of Cracow. This assessment was done using control
charts x for 59 observations. The analysed research period covered the
multi-year from 2012 to 2016. Five key pollutant indicators were used to
evaluate the work of the tested object: BOD5, CODCr, total suspension,
total nitrogen and total phosphorus. In the case of the majority of
them, based on the analysis of control charts, full stability of their
removal was found in the tested sewage management facility. The
exception was total nitrogen, for which periods of disturbed stability
of its disposal processes were noted. Analysis of the effectiveness of
wastewater treatment showed each time that the required efficiency of
reduction of the analysed pollution indicators in the “Kujawy” Sewage
Treatment Plant was achieved.